Traveling-grate furnace



(No Model.) 2 Sheets-Sheet 1, E. B. OOXE. TRAVELING GRATB FURNACE.

N0. 510,575. Patented Dec. 12, 1893.

I aI

n1: NATIONAL LITNOGHAPNING COMPANY.

WASHINGTON. n. c

UNITED STATES PATENT FFICE.

ECKLEY B. COKE, or DRIFTON, PENNSYLVANIA.

TRAVELlNG-GRATE FURNACE.

SPECIFICATION forming part of Letters Patent No. 510,575, dated December12, 1893.

Application filed July 14:. 1893.

To all whom it may concern:

Be it known thatl, EOKLEY B. COXE, a citizen of the United States,residing at Drifton, in the county of Luzerne and State of Pennsylvania,have invented certain new and useful Improvements in Traveling-GrateFurnaces, of which the following is a specification.

This invention relates to traveling-grate furnaces of the classdescribed in the prior Letters Patent No. 499,716, granted to me J one20, 1893; the object being to provide means for properly regulating thesupply of fuel to the middle portion and edges of the travelingfurnace-floor, for preventing the premature burning-out of the fuelalong the edges of the furnace-floor.

In the drawings accompanying and forming a part of this specification,Figure 1 is a plan view of a portion of a furnace embodying my presentimprovements. Fig. 2 is a sectional side elevation of the furnace. Fig.3 is a sectional view, in line a" a Fig. 2, showing the parts at theright-hand of said line as seen from a point at the left-hand thereof.Fig. 4 illustrates a modification of the furnace. Fig. 5 is a plan Viewof the adjustable fuel-gate, and Fig. 6 is a side view of said gate.

Similar characters designate like parts in all the figures.

The furnace shown in the drawings for illustrating the nature and modeof operation of my present improvements, is similar to that shown in myaforesaid Letters Patent, with the exception of certain features shownin Figs. 1, 2, 3 and 4, and referred to in my concurrent application,Serial No. 472,891, filed May 3, 1893.

The furnace illustrated in the drawings is shown underneath asteam-boiler, B, which maybe of any well-known type; or, said boiler maybe replaced by any other thing to be heated. The furnace has the usualinclosing-walls at the sides and ends thereof, and (in the absence of asteam-boiler or other device to be heated over the furnace) the ordinarytop-oovering. In the drawings, the sidewalls are designated in a generalway by 2 and 3, respectively, and the furnace-chamber, O, is showncovered by a steam-boiler, B. At the forward end of the furnace-chamber,this is provided with the end-wall, 4, through Serial No. 480,491. (Nomodel.)

ing a chute comprising the inclined and lower wall 5", for deliveringthe fuel from the hopper tothe grate G.

The under side, or floor, of the furnacechamber 0 is formed of thefuel-carrying run,

10, of an endless traveling grate, designated in a general way by G, andpreferably composed of a series of similar grate-bars, or sections, 9,pivotally connected and carried by the wheels 12 and 14, that are fixedon the two shafts 13 and 15, respectively. The ends of the severalgrate-bars are shown supported by guides of which those for the upper orfuel-carrying run of the grate are designated by 16 and 18, while thosefor the lower or re turn-run 11 are designated by 17 and 19,respectively. A suitable construction of the grate-bars is shown indetail in my aforesaid Letters Patent, to which reference may be had. Inthe under side of the grate-bar, or grate-section, there is formed inthe end-bars thereof the notches 30 for engaging the corresponding cogs33 of the chain-wheels 12 and 14, when the grate is driven forward.

For protection, in practice, of the ends of the grate-bars,'andalso forpreventing the fine fuel passing over the ends thereof, the side-wallsof the furnace are brought over the grate-bars substantially as shown inthe sectional view, Fig. 3, the brick-supporting plates, 20 and 22, ofthe side-wall extending over the grate-bar by a distance equal to, orgreater than, the width of the'end-bar 29 of the grate-section.

Under the upper or fuel-carrying run, 10, of the traveling-grate is aseries of air-supply chambers, a, b, c and d, located at successivepoints of the length of the furnace-chamber. The air-supply chambers maybe two or more in number, four of them being shown in the presentinstance; in general, I prefer to use not less than three such'chambers.Each of said successive chambers is to be suitably supplied with air,which may be done by blowing the air thereinto through correspondingpipes, a, b, c and (1', shown in end view in Fig.2, after the mannerdescribed in my aforesaid Letters Patent No. 499,716.

The fuel is fed to the grate ata point adjacent to the first air-supplychamber, each section of the grate receiving its fuel at or before thetime it reaches the first air-supply chamber a, being then carried alongover that chamber and the succeeding chambers I), c and (Z; during thisperiod the combustible material of the fuel is consumed, and theresulting cinder or ash is afterward carried under the bridge-wall 7 andfinally delivered over the rearward end of the grate into the ash-pit21. In practice, the combustion goes on, at one stage or another,throughout nearly the entire length of the furnace, the ignition takingplace within a short distance of the point Where the fuel falls upon thegrate, this being completely reduced to cinder over the last chamber, d,of the series. The reduction of the fuel by combustion gradually lowersthe same on the grate, (by an amount depending on the nature of thefuel,) so that at the point, 23, where the cinder passes under thebridge-wall, the thickness of the cinder is generally much less than theoriginal height of the fuel, as illustrated in Fig. 2.

In Figs. 2 and 3, the fuel is delivered to the grate over an inclinedignition-block 6, after the manner described and claimed in my saidapplication, Serial No. 472,891. In Fig. 4,, an arrangement is shown fordelivering the fuel directly onto the grate from the hopper; but in eachcase the construction and mode of op eration of the grate G are, (or maybe) the same.

It will he remembered that the class of furnace herein referred to isespecially designed for use in burning the finer sizes of anthracitecoal. This kind of fuel, when supplied to the grate in a layer andcarried forward on. the grate adjacent to the fixed side-walls 2 and 3,partakes, in the portion thereof im' mediately adjacent to said walls,of the character ofa flowing stream, the particles con tiguous to thewalls being held back by the friction of the mass against the surface ofthe wall, while the fuel on the middle portions of the grate is carriedforward at the full speed of the traveling-grate. The natural result ofthe described action is to burn out the fuel along the edges of thegrate more rapidly than over the middle portions of the same, and thus,by lightening the weight of ash and cinder on the border-portions of thegrate, permit the airblast to form openings through which it may escapeinto the furnacechamber without passing through the heavier unconsumedfuel on the middle portions of the furnace-floor.

For overcoming the defective operation above mentioned, I provide meansfor distributing along the edges of the furnace-floor an extra supply offuel, so that, notwithstanding its lesser rate of movement, it will beburned up in substantially the same time as required for the burning ofthe relatively thinner mass upon the middle portions of the grate. As ameans for effecting this object, I provide an adjustable fuel-gate Ehaving means for raising and lowering the same and constructed at itslower edge for delivering fuel to the extreme edge portions of thetraveling-grate at a greater depth than to the middle portions thereof.The preferred construction here referred to of the fuel-gate E, isillustrated in Figs. 3 and 6; the latter figure by means of the dottedlines at the lower corners thereof, shows the spaces 25 and 26 formed bycutting away the gate, for permitting the passage thereunder of therequired extra supply of fuel. Said extra supply, being delivered to thegrate as specified, is carried along adjacent to the side-walls 2 and 3of the furnace in the form of a ridge or elevation. Indicated a 27 inFigs. 2, 3 and at.

In Fig. 2, the elevation, asindicated by said line 27 of said extraedge-supply of fuel, is gradually reduced as the grate passes from theright-hand toward the left-hand of the f urnacecham her, until the depthof said edgesupply of fuel coincides with the depth of the fuel upon themiddle portions of the grate; this reduction of depth resulting, ashereinbefore set forth, from the retardation of the particles by thefriction of the same against the side-walls of the furnace.

The means herein shown for adjusting the fuel-gate E consist of theelevating-screws 28 and 29 which are journaled in the bearings 33 and34, respectively, of said gate, and work in the threaded bearings fixedon the hopper II at 31 and 32, as indicated in the drawings. Said screws28 and 29 are each shown provided with a suitable hand-wheel 30 wherebyto turn the same for raising or lowering the gate as may be required. Inpractice, the two gate-actuating devices here described may be connectedfor simultaneous operation, in a well-known manner.

Having thus described my invention, I claim- 1. In a travelingratefurnace, the combination with a traveling-grate orfurnace-l'loor, andwith the sidewalls of the furnace, of a fuel-supply, and a fuel-gatehaving an increased opening thereunder at the side of thefurnace-chamber, whereby an extra supply of fuel is delivered to theedge-portions of the grate contiguous to the side-walls of the furnace,substantially as described and for the purpose set forth.

2. In a traveling-grate furnace, the combination with a traveling-grateor furnace-floor, and with the side-walls and fuel-supply, of thefuel-gate adjustably supported and having its edge reduced at the endsthereof to provide a widened fuel-passage, as set forth.

ECKLEY B. OOXE.

\Vitnesses:

STEWART F. MAOFARLANE, ELLIOTT A. OBERRENDER.

